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Full text of "The manufacture and properties of iron and steel"

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from 21 to 37 per cent., and in the dry state from 21 to 45 per cent. The ore is sorted by hancl-and-eye inspection, and the average product in a dry state carries 34 per cent, of iron with 6 per cent, of silica and 28 per cent, of carbonic acid and lime, the latter making the ore self-fluxing. It is even a little too calcareous and needs mixing with a silicious ore. Its value is given as 75 cents at the mines. The ore was once a carbonate, but by exposure has changed to a hydratcd peroxide and is used without calcining. Northampton raises an increasing amount of a lean and silicious iron ore, some of which is smelted near by, and the rest sent to Staffordshire and elsewhere. The ore gives 38 per cent, in the pig-iron, and is worked in the open from a bed 18 feet thick. After paying royalty the ore can lie delivered at near-by furnaces for 65 cents per ton. This gives a cost of $1.70 for the ore per ton of pig-iron, but the high silica renders the smelting costly.
The deposits in this part of England are related geologically to the Cleveland beds and may be looked upon as the southern outcrop. The use of these lean ores is a recent development, just as in Luxemburg the Minette deposit has come only recently into prominence. In 1830 there were only 5300 tons of iron made from the lean ores of Cleveland and Lincolnshire. In 1860 Cleveland mined 1,480,000 tons of ore, and by 1870 this had risen to 4,300,000 tons, and by 1880 to 6,260,000 tons. The increase has not continued in
TABLE XXTII-V. Output of Ore and Pig-iron in Eastern Central England.
	Ore Raised.				Pig Iron.		
AvorARO for period							
per year ; tone.	Leicester.	Lincoln.	Northampton,	Total.	Lincoln and Leicester.	Northampton.	Total.
1882 to 1885 inclusive.	283,748	1,233,075	1,265,739	2,782,602	233,352	198,807	432,159
1886 to 1890 InduHivc,	498,428	1,291,560	1,105,824	2,806,797	279,493	225,390	504,483
]!)] to 1H!!5 inclusive.	502,957	1,864,279	1,019,200	2,976,436	294,749	198,824	493,573
1896 to I!X)0 IncluHlvo. 1901 to 191)3 Inclusive.	708,iJ77 670,7(58	1,841,065 1,747,209	1,407,303 1,705,000	4,017,725 4,129,847	38(1,815 864,785	360,406 235,(539 .	641,281 600,424
Cleveland, which in 1903 mined only 5,677,560 tons, but the mines of the southern district are coming to the front. In 1860 this region raised only 118,000 tons; in 1870, 1,048,000 tons; in 1880, 2,766,000 tons; while in 1903 the output of the three counties of